Lout is a document formatting system similar in style to LaTeX. It offers a very full range of features, including both PostScript and plain text output, optimal paragraph and page breaking, automatic hyphenation, PostScript EPS file inclusion and generation, equation formatting, tables, diagrams, rotation and scaling, sorted indexes, bibliographic databases, running headers and odd-even pages, automatic cross referencing, multilingual documents including hyphenation (most European languages are supported, including Russian), formatting of C/C++ programs, and more. Lout may be extended by writing definitions which are much simpler than the equivalent troff of TeX macros. Lout is written in highly portable ANSI C and runs on most platforms. It is distributed under the GNU public license. Its primary web site is ftp://ftp.cs.su.oz.au/jeff/lout/ Consult the README file in that directory for information about the latest version. Lout was designed and implemented by Jeffrey H. Kingston (jeff@cs.su.oz.au) of the Basser Department of Computer Science at the University of Sydney.